class_docstr: DAGRepr test
class_docstr_tok: ["DAGRepr","test"]
code: def test_dag(self):
      dr = DAGRepr.from_dict(self.dag_dict)
      edges = dr.edges
      nodes = dr.nodes
      dag_dict = dr.dag_dict
      top_sort = dr.top_sort
      self.assertEqual(len(edges), 5)
      self.assertEqual(len(nodes), 4)
      self.assertEqual(len(dag_dict), 4)
      self.assertEqual(len(top_sort), 4)
      for edge in edges.values():
          for schema in edge["schema"]:
              self.assertTrue(
                  isinstance(edge["schema"][schema], SchemaRepr)
              )
      for node in nodes:
          self.assertTrue(isinstance(dr.nodes[node], NodeRepr))
  
      dr = DAGRepr(nodes=nodes, edges=edges)
      edges = dr.edges
      nodes = dr.nodes
      dag_dict = dr.dag_dict
      top_sort = dr.top_sort
      self.assertEqual(len(edges), 5)
      self.assertEqual(len(nodes), 4)
      self.assertEqual(dag_dict, None)
      self.assertEqual(len(top_sort), 4)
  
file_path: towhee/tests/unittests/runtime/test_dag_repr.py
imports: import copy
  import unittest
  from towhee import pipe
  from towhee.runtime.dag_repr import DAGRepr, NodeRepr
  from towhee.runtime.data_queue import ColumnType
  from towhee.runtime.schema_repr import SchemaRepr
label_desc: Use image node_id 1 for calling the TestDAGRepr obj's underlying member method code with example usage: obj.test_dag() without return types